Currently no satisfactory, objective indicia of pain exist for determining the existence of or the extent of pain experienced by a subject. While various imaging technologies exist for the diagnosis and observation of various conditions and diseases, the capability for using such technologies for identifying and imaging pain does not currently exist. The ability of a physician to confirm a patient's complaint of pain and to determine the extent and possibly the nature and/or source of such pain would provide a significant advantage to the field of medicine in general and to the growing field of pain management in particular.
In the clinical world, physicians currently use tools such as the “Visual Analog Scale” to help determine a patient's pain experience relative to their own prior experiences. However, these evaluations cannot be normalized across human subjects. In the clinical imaging world, there are some studies using functional magnetic resonance imaging and brain positron emission tomography (PET) to image painful stimuli. However, these are restricted to the study of the brain only and do not give insight into the peripheral stimuli (a.k.a. drivers) of these unpleasant experiences.
Many patients suffer from conditions associated with atypical and/or generalized pain, such as fibromyalgia, reflex sympathetic dystrophy, peripheral nerve entrapment syndrome and chronic fatigue syndrome, where the source/cause of the pain may not be capable of determination. It can be discouraging for both the doctor and patient to be unable to confirm the patient's symptoms and/or locate the source of the pain for treatment purposes. Thus, there is a need for a technology that offers the ability to identify and measure pain and to help locate the source of the pain and/or offer treatment options. Additionally, such technology would be useful for studying various aspects of pain, such as its mechanisms, the physiological pathways associated with pain and its manifestation, and variances in the experience of pain among different subjects. Such technology would also be useful for imaging and studying conditions characterized by pain-like sensation or loss of sensation, such as spinal cord injury or compression, various neuropathies, and myelitis.
Similarly, it is difficult to objectively determine and/or measure a patient's stress level and to treat and/or prevent other medical conditions, both mental and physical, associated with elevated stress levels. The ability to image the existence of and/or the extent of stress experienced by a patient would provide numerous advantages in the field of psychiatry and psychology. This ability would provide doctors and researchers with new tools for studying the causes and physiological effects of stress, its biological manifestations, and to evaluate the effectiveness of various treatments. It may also allow detection and diagnosis of extreme or chronic stress in a subject, and thereby open the door to treating the stress before it leads to other conditions or disorders, such as hypertension, depression, and other associated conditions.
In addition, since non-human subjects are unable to communicate the existence of pain, or its source, a technology that provides the ability to image pain would offer a significant advantage in the veterinary field. It is also difficult to diagnose stress in such subjects, and not much is known about the existence, experience of or sources of stress in non-human subjects. Therefore, the ability to objectively determine the existence of stress in such subjects would provide numerous advantages, including the ability to diagnose and treat stress in non-human subjects, as well as the ability to study the condition.